Cyanobacteria from the Middle Xingu River (Pará, Brazil):updated checklist and occurrence patterns

Abstract

Cyanobacteria are widely distributed, occurring in marine environments, inland waters, soils, and extreme environments, and occupying various ecological niches. Many species have the potential to form toxic blooms, highlighting the importance
of floristic studies for aquatic biodiversity. The objective of this study was to present an updated list of cyanobacterial species in the Middle Xingu River, Pará, Brazil. Sixty-two microphytoplankton samples collected at six stations on the left bank of the Xingu River, in the urban area of Altamira, in the years 2010, 2011, 2012, 2019, 2022, 2023, and 2024, were analyzed. A total of 57 species of Cyanophyceae were recorded. The most representative families were Microcystaceae, Aphanizomenonaceae, and Oscillatoriaceae, and the genera with the greatest diversity were Aphanocapsa, Microcystis, Aphanothece, and Dolichospermum. The results expand our understanding of regional diversity and support environmental monitoring studies.